1. Field of the Invention
The invention relates in general to a method and apparatus for driving an SATA hard disk, and more particularly to a method and apparatus for driving a non-native SATA hard disk.
2. Description of the Related Art
A serial ATA (SATA) hard disk is for replacing a conventional parallel ATA (PATA) hard disk. The PATA hard disk adopts a parallel transmission, so the PATA hard disk requires more pins and a wider cable line. Moreover, the length of the cable is restricted in order to achieve a synchronized transmission. On the other hand, the SATA hard disk adopts a serial transmission, so the number of pins used is smaller, the cable line can be longer and the assembly is easier. Moreover, the speed of the SATA hard disk is as fast as 150 MB/s and may be further speeded up by means of multi-linking.
During the transitional period from the PATA hard disk to the SATA hard disk, native SATA hard disk is still lack of a matured technology, so non-native SATA hard disk is used as a transitional product. The non-native SATA hard disk uses the same interface with the native SATA hard disk and has the same feature of using fewer pins. However, unlike the native SATA hard disk, the non-native SATA hard disk adopts a PATA internal disk and uses a conversion interface disposed within to convert a serial SATA signal into a parallel PATA signal and vice versa.
FIG. 1 is a block diagram of a non-native SATA hard disk. Non-native SATA hard disk 100 includes a conversion interface 101 and a PATA internal disk 102. The non-native SATA hard disk 100 has a serial cable 103 through which a serial SATA signal is transmitted to or received from a computer. The PATA internal disk 102 has a parallel cable 104 through which a parallel signal is transmitted to or received from the conversion interface 101. The conversion interface 101 is a bridge connecting the PATA signal and the SATA signal.
When a conventional PATA hard disk is used, the operating system needs to set a timing mode for the PATA hard disk and the hard disk host. The timing mode, which shows the transmission speed between the PATA hard disk and the hard disk host, has various modes listed in ascending order of transmission speed as follows: PIO modes 0˜4, Multi-word DMA modes 0˜2, Ultra DMA modes 0˜6. The BIOS inquires the type of the PATA hard disk and the timing mode supported thereby when a computer is booted.
After the computer is booted, the operating system (OS) sets appropriate timing according to the mode supported by the hard disk host and the mode supported by the PATA hard disk.
Unlike the PATA hard disk which requires the setting of timing mode, the SATA hard disk does not require the setting of timing mode because a packed type of transmission is adopted. The non-native SATA hard disk has a PATA internal disk disposed within, so the setting of timing mode is still required of the PATA internal disk inside the non-native SATA hard disk. However, ordinary BIOS and OS only regards the non-native SATA hard disk as an native SATA hard disk and will not automatically set the PATA internal disk inside the non-native SATA hard disk. The non-native SATA hard disk still can be used despite that the timing mode of the PATA internal disk is not set. Under this circumstance, the PATA internal disk will operate under a default mode, a PIO mode 0 for instance, reducing the speed of data accessing.
FIG. 2 is a conventional method of driving a non-native SATA hard disk. First, in step 110, the BIOS enters into a power on self test (POST) stage for initializing the peripheral of the computer such as display card, memory, central processing unit and hard disk when the computer is booted, then the BIOS calls an SATA option ROM provided by the manufacturer of the non-native SATA hard disk. Next, go to step 120: the OS is booted. After that, go to step 130: the OS loads the SATA driver provided by the manufacturer, so the operating system may access the SATA hard disk with best efficiency by means of the SATA driver provided by the manufacturer. However, such a practice requires the manufacturer of the non-native SATA hard disk to develop an SATA option ROM and an SATA driver, not only increase costs and time with regard to research and development, but also needs additional purchasing cost of the SATA driver and SATA option ROM, leading to an increase in manufacturing costs of the system manufacturer.